Improvement in sharpeners for harvester-knives



H. FISHER.

Improvement in Shapeners for Harvester-Knives.

N0. 128,957. Patented]uIy16,1872.

rrnn STATES? TENT Orrron.

HENRY FISHER, OF CANTON, OHIO.

Specification forming part of Letters Patent No. 128,957, dated July 16, 1872.

SPEOIFIOATION.

To all whom it may concern:

Be it known that I, HENRY FrsnER, of Canton, in the county of Stark and State of Ohio, have invented certain new and useful Improvements in Sharpening Harvester-Knives; and that the following is a full, clear, and exact specification thereof, which will enable others skilled in the art to make and use the said invention.

Most of the devices for sharpening harvester-knives heretofore invented present several objections in practical use, among which is the Want of portability, which makes it practicable to carry the sharpening mechanism on the machine, so as to be available in the field, thus reducing the mechanism to a stationary shop device, which is little better than the common grindstone with a device for holding the knives at a proper angle.

Such devices ashave been heretofore invented with a view to portability have been found to be unsatisfactory, for the reason that the device failed to produce a good cutting-edge, which was the case with those devices consisting of two bars of steel placed at an acute angle with each other, and operated by being drawn over the edge of the knives; or for the reason that the knives were worn off at too obtuse an angle, and with such irregular edges as to make them cut badly while at work, and to render them very difficult to grind properly on a grindstone, which was the case with those sharpening devices consisting of a whetstone held at one end by the hand of the operator, and rubbed over the inclined faces of the knives. In the last-named class of sharpening devices, in addition to the objections already stated, the time required to sharpen all the knives on the knife-bar in the ordinary manner of using a whetstone is almost an insuperable objection to its use, and the want of any convenient means of holding the knife-bar, except in its ordinary position in the fingerbar, where the fingers interfere with sharpening the whole length of the knife-edge, is also a serious objection to this plan. My invention is designed to obviate the objections to this last-mentioned plan,which I consider the only practical plan of sharpening the knives in the field; and to this end it consists in the construction of a whetstone or emery-block holder, composed of a ribbed back piece, having a head-block and handle at one end, and asecond handleprovided withasuitable clamping device at the other end; said holder being used in combination with a whetstone or emery-block, which is held within the headblock and clamping device of the holder, and which bears on its upper side against the back piece of said holder so as to be supported by said back piece from breaking. The said holder having the whetstone or emery-block arranged in it, as just described, is grasped by the operator by one hand at each handle, and is thus held so as to move at a constant angle while sharpening the knives, and also so as to be borne upon with considerable power in order to facilitate the process-of sharpenin g the support due to the bearing of the stone or emery-block on the back piece of the holde'r, preventing any danger of breaking the stone or block by the pressure of the operator on the handles at its ends.

In the accompanying drawing, Figure 1 is a perspective view, showing myimproved holder and its application. Fig. 2 is a side view of said holder. Fig. 3 is a cross-section of the same on the line 00 w in Fig. 2. Fig. 4 is an end view of an application of said holder.

The back piece K of the holder is convenient- 1y made of malleable cast-iron, and is constructed with a vertical rib, is, in order to give it sufficient stifi'ness, with a light weight of metal to resist deflection from the pressure on the handles at its ends. The head-block 7c is formed at one end, and back of this head-block is socured the handle 13, which may be driven onto a tapering spindle formed on the end of the back piece K. At the other end of the piece K is formed the lug 6, through which-runs the threaded rod I, having a loose head at its front end and having the handle B secured on its other end. The whetstone or emery-block A (the whetstone usually being preferable, as it is less liable to gum in working on harvester-knives) is placed in the above-described holder with its end against the head block k and its upper face against the back piece K, and is held in this position by turning the handle B so as to press theloose head of the threaded rod I firmly against the end of the stone or block A, thus clamping said stone or block betwcfen the head block k and loose head on the ro I.

The harvester-knife or cutter-bar Sis conveniently held in position to be operated on with said holder and stone by means of two portable clamps, NOB, consisting of a pointed standard, N, which can be driven into any solid support, M, and at the. head of which is a broad face, 0, through which passes the bolt L having a rectangular head, It, at one end, and a thumbscrew, 1r, at the other. Two of these clamps having been driven into the support M, as shown in Fig. 1, the back T of the knife-bar can be clamped between the heads B and faces 0 in either of the positions shown in Figs. 1 and 4, in a manner readily seen, thus holding the knife in a convenient position for sharpening.

The operator grasps the handles B B at each end of the holder, and works the stone A over the knives in the manner indicated in Figs. 1 and 4 and it will be evident that by having a firm grasp with each hand at the ends of the holder he will be enabled to work the holder at amuch more unform angle than if held at one end only, for the same reason that the mechanic can file more evenly by grasping the file at both ends than he can by holding it only by one end, while it will also be seen that owing to the support given to the stone A by the back piece K said stone maybe used until worn down quite thin, which would otherwise be quite impracticable, while a much greater pressure may be applied to the hanstone, except when constructed with a broad,

fiat, cast-metal back piece, to give full lateral support to the stone; a rib on said back piece to give it requisite stiffness, with a light weight of metal to resist bending from pressure on the end handles; and a clamping-screw with handle at one end and loose head at the other, to serve as the clamping device for holdin g the stone; as I am aware that stone hol ders with a round rod for back piece, and with handles at each end, have been before shown.

What I claim as my invention is- The herein-described stone-holder, consisting of the flat castmetal back piece K, having the rib K and head-blocks 7a 11 cast therewith, and provided with the handle B at one end, and of the clamping-screw I working through the head-block z, and provided with loose front head and fixed handle B, said holder having the stone A arranged and held therein, as and for the purpose specified.

HENRY FISHER.

Witnesses:

J OB ABBOTT, J ENNIE M. GRANT. 

